Filter a Matrix to show months with zero

Hi MartinJoughin ,

According to your statement, I think you want to show the clients who have blank data in matrix.

Here I use  Jihwan_Kim's sample to create a measure.

Measure = 
VAR _GENERATE =
    GENERATE (
        CALCULATETABLE ( VALUES ( client[client] ), ALLSELECTED(sales)),
        CALCULATETABLE (
            VALUES ( 'calendar'[Year-Month] ),
            ALLSELECTED(sales)
        )
    )
VAR _SALES =
    ADDCOLUMNS (
        _GENERATE,
        "Sales",
            VAR _client = [client]
            VAR _YearMonth = [Year-Month]
            RETURN
                CALCULATE (
                    SUM ( sales[sales] ),
                    FILTER (
                        ALLSELECTED(sales),
                        sales[client] = _client
                            && FORMAT ( sales[date], "YYYY-MMM" ) = _YearMonth
                    )
                ) + 0
    )
VAR _SUMMARIZE =
    SUMMARIZE (
        _SALES,
        [client],
        "Product", PRODUCTX ( FILTER ( _SALES, [client] = EARLIER ( [client] ) ), [Sales] )
    )
RETURN
    SUMX ( FILTER(_SUMMARIZE,[client] = MAX(client[client])), [Product] )

Add this measure into visual level of matrix visual and set it to show items when value = 0.

Before:

Result is as below.

Best Regards,
Rico Zhou

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